Experimental infection of pig-tailed macaques (Macaca nemestrina) with Campylobacter cinaedi and Campylobacter fennelliae.

Campylobacter cinaedi and C. fennelliae have been associated with proctocolitis, bacteremia, and asymptomatic rectal infection, primarily in homosexual men. To more directly assess the pathogenic role of these organisms, we studied their disease-producing potential in 12- to 25-day-old pig-tailed macaques (Macaca nemestrina). Four infant monkeys were challenged with 10(8) to 10(9) C. cinaedi, three were challenged with C. fennelliae, two were challenged with C. jejuni, and one received no microorganisms. Watery or loose stools without associated fever or fecal leukocytes developed 3 to 7 days postinoculation in all of the animals given C. cinaedi, C. fennelliae, and C. jejuni, but not in the control animal. Stool cultures were simultaneously positive and remained so in the animals challenged with C. cinaedi or C. fennelliae for 3 weeks after inoculation despite the resolution of clinical illness. All of the animals challenged with C. cinaedi and C. fennelliae became bacteremic, and three had clinical evidence of septicemia. Histopathologic evaluation of rectal biopsies (five animals) and necropsy (one animal) showed no evidence of mucosal disruption. Specific immunoglobulin M and immunoglobulin G antibody responses occurred in all of the animals challenged with C. cinaedi and C. fennelliae, as determined by enzyme-linked immunosorbent assay and immunoblotting. We conclude that C. cinaedi and C. fennelliae consistently produce a diarrheal illness accompanied by bacteremia and followed by prolonged gastrointestinal colonization in M. nemestrina.     

Evidence of reinfection with multiple strains of Campylobacter jejuni and Campylobacter coli in Macaca nemestrina housed under hyperendemic conditions.

A prospective bacteriologic study of 18 infant pig-tailed macaques (Macaca nemestrina) housed in a nursery facility in which Campylobacter spp. are endemic was undertaken to determine the epidemiology of infection and reinfection. The isolates of Campylobacter jejuni and C. coli cultured from 8 of the 18 infants were characterized by serotyping, DNA hybridization, and polyacrylamide gel electrophoresis protein profiles. The chronology of infection was indicative of multiple reinfections with different strains of C. jejuni and C. coli during the 12-month study of each infant. The duration of infection with a particular strain was 3 to 4 weeks. Infants were also infected with nalidixic acid-resistant campylobacters. These observations indicated that long-term infections under endemic conditions are caused by continual reinfection. C. jejuni or C. coli infection correlated with diarrhea in 5 of the 18 infants at 1 to 4 months of age.     

Uncommon Campylobacter species in infant Macaca nemestrina monkeys housed in a nursery.

Studies were conducted to characterize 18 isolates of Campylobacter spp. that could not be identified as either Campylobacter jejuni or C. coli. The isolates were cultured from specimens from 13 of 18 infant nonhuman primates during a prospective epidemiologic study reported previously. Phenotypic tests, DNA hybridization, and analysis of DNA coding for rRNA identified the isolates as C. butzleri (seven isolates), C. hyointestinalis (seven isolates), and C. fetus subsp. fetus or C. fetus subsp. fetus-like organisms (four isolates). Ribotype and polyacrylamide gel electrophoresis patterns indicated that there was heterogeneity among the isolates of C. butzleri and C. fetus subsp. fetus-like organisms.     

Campylobacter pylori isolated from the stomach of the monkey, Macaca nemestrina.

Campylobacter pylori was isolated from the gastric mucosa in 6 of 24 pigtailed macaques (Macaca nemestrina) examined by gastric biopsy and culture; 3 isolates were recovered during gastroendoscopy, and 3 were recovered at necropsy. The isolates were morphologically and biochemically similar to the human type strain NCTC 11638, differing only in colony diameter, pigmentation, and rate of growth. Identity of the isolates was confirmed by whole-genomic DNA-DNA hybridization with the type strain. Colonization of the monkey stomachs was associated with hypochlorhydria and histologic features resembling type B chronic gastritis in humans. Host animals exhibited no morbid clinical effects of colonization, although endoscopy revealed inflammation, erythema, and friable tissue in some animals. The discovery of C. pylori occurring spontaneously in M. nemestrina extends the known range of the hosts of the organism and offers the possibility of a natural or experimental model of the infection in monkeys.     

Campylobacter jejuni infection occurring during pregnancy

Campylobacter infections occurring during pregnancy have been associated with spontaneous abortion, stillbirth, prematurity and neonatal sepsis, all tenCampylobacter jejuni infections diagnosed in the approximately 24,000 pregnant women attending a 520-bed hospital between January 1984 and December 1988 were reviewed. Nine women delivered healthy babies at term. In one case,Campylobacter infection at 28 weeks of gestation was associated with premature labour and delivery with subsequent neonatal sepsis and death. One other infant developedCampylobacter jejuni enterocolitis at 3 days of age. Although maternalCampylobacter jejuni infection tends to be mild and self-limited, there may be more serious complications for the fetus or neonate, especially if infection occurs before the third trimester of pregnancy.     

Serological response to Campylobacter jejuni/coli infection.

The antibody response to Campylobacter jejuni/coli infection was investigated in 59 patients involved in two outbreaks of milk-borne infection and in sporadic infections in the community. Agglutinins and complement-fixing (CF) antibodies were detected in nearly all these patients. Agglutinins were present in 25% of normal sera at low titres (not greater than 1/160) but CF antibody titres of 1/4 or 1/8 were present in only 2.0%. The agglutination reactions in convalescent sera were best developed with the homologous or an antigenically similar strain whereas the CF test, with sonicated organisms as antigen, was less strain-specific and was more suitable as a routine test. Antibody was present seven to 10 days after the onset of symptoms.     

Fatal Campylobacter jejuni infection in a patient splenectomised for thalassaemia.

A 35 year old man with a fatal Campylobacter jejuni infection is described. He had HbE/beta zero thalassaemia and had undergone splenectomy nine months previously for hypersplenism; he also had chronic hepatitis C infection. He presented with high grade fever but no gastrointestinal symptoms and rapidly progressed to septicaemic shock and hepatic encephalopathy despite treatment with penicillin, gentamicin, and, later, chloramphenicol and ceftazidime. Only one case of Campylobacter jejuni septicaemia occurring post-splenectomy has been reported previously, also in an iron overloaded thalassaemia patient. Unusual Gram negative bacilli must be covered by the chosen antibiotic regimen when splenectomised thalassaemic patients present with high grade fever.     

Experimental Campylobacter jejuni Infection of Adult Mice

HA-ICR adult mice were studied to develop an animal model for Campylobacter jejuni enteritis in humans. Fecal and ileal cultures made by selective and nonselective methods showed that C. jejuni and related organisms are not bowel commensals. Intragastric feeding of 10⁸ CFU of three different strains of C. jejuni produced infection in 100% of the animals, and infection rates were dose dependent. Pretreatment with antibiotics or opiates was not necessary to induce infection. Fresh isolates and strains passed on artificial media yielded similar infection rates. Infected mice did not show signs of illness, but transient bacteremia within 10 min of oral infection was observed in nearly 100%. The small intestine was the principal target organ, with epithelial inflammation seen 48 h after infection. Control mice of four species had undetectable serum immunoglobulin G antibody specific for the infecting strain, but infected mice showed peak titers at 1 week with rapid decline. Immunoglobulin M titers rose minimally, and immunoglobulin A titers did not rise. Infected mice uniformly became chronic asymptomatic excretors, shedding 10⁴ to 10⁶ CFU/g of feces; a minority were biliary carriers. Intestine carriage was most pronounced in the stomach and proximal small intestine. Because this experimental infection led to bacteremia, transient pathological changes, and immunoglobulin G titer rises, this model may be useful for evaluating the effects of prophylactic and therapeutic interventions.     

Experimental gastroenteritis in newly-hatched chicks infected with Campylobacter jejuni

The susceptibility of chicks to enteritis caused by Campylobacter jejuni was studied. Three-day-old chicks did not develop enteritis after oral infection but chicks infected within 12 h of hatching developed gastroenteritis. The incubation period correlated with the inoculum size. Initially, infected chicks developed blood- and mucus-containing stools, although watery diarrhoea often occurred late in the course of the disease. Recurrences of the enteric manifestations were common but only two out of 170 infected chicks died. C. jejuni was recovered from sites throughout the intestine; the highest concentrations were present in the caecum and large intestine. Both the upper and lower gastrointestinal tract were affected and cellular infiltration of the gastric mucosa and the intestinal lamina propria was observed. Organisms resembling C. jejuni were seen within the intestinal epithelium and lamina propria by electronmicroscopy. The newly hatched chick provides a reproducible and sensitive model of campylobacter enteritis.     

Experimental infection of chickens with Campylobacter jejuni: strains differ in their capacity to colonize the intestine.

Groups of broiler and layer type chickens (25 to 63 d.o.) were inoculated per os with separate isolates of 10 strains of Campylobacter jejuni. Nine of the 10 strains were originally isolated from chickens and one from a dog. The dog strain and five of the chicken isolates could be isolated after inoculation, but four strains were not recovered from cloacal swabs for up to 4 to 16 days after inoculation. However, it was possible to isolate C. jejuni from these birds, from cloacal swabs, when they were inoculated with organisms which had been previously shown to colonize other birds.     

Morphologic observations of experimental Campylobacter jejuni infection in the hamster intestinal tract.

The authors have developed a model for the diarrhea and intestinal lesions seen in Campylobacter jejuni enterocolitis by colonizing the hamster ileum and cecum with C jejuni. Erythematous inflammation of the ileum and cecum and distention of the cecum with fluid were observed at autopsy. The cecal mucosa appeared edematous. Epithelial abnormalities observed by light microscopy included focal edema, occasional hyperplasia, diffuse hyperemia, and infiltration of the lamina propria with leukocytes. C jejuni-like bacteria penetrated the epithelium and were seen in the lamina propria of infected animals but not in uninfected controls. Diverse microvillus lesions, including elongation, shortening, blebbing, and denudation, were seen by transmission electron microscopy. Occasional cytoplasmic aberrations included vacuoles, some containing C jejuni-like bacteria, swollen endoplasmic reticulum, and enlarged mitochondria. Campylobacter structures were vibrio and S-shaped types. Some C jejuni organisms had corrugated screwlike structures wrapped around their circumferences.     

The influence of age on Campylobacter jejuni infection in chicken

Campylobacter jejuni (C. jejuni)-host-interaction may be affected by the maturation stage of the chicken's immune system and the developing gut microbiota composition. We compared these parameters between birds C. jejuni-inoculated at day one, 10, 22 and 31 post hatch. The highest C. jejuni-colonization rate and numbers of colony forming units (CFU) were detected in caecal content of day-one-inoculated birds while the lowest was detected in 22-days-old birds. The low bacterial colonization of 22-days-old chickens correlated with the most prominent immune reactions in this age group in comparison to other age groups. Age and C. jejuni-inoculation had a significant effect on lymphocyte numbers and cytokine expression levels in caecum as well as on gut flora composition. Overall, the immune response to C. jejuni is significantly influenced by the age of the infected chickens leading to differences in C. jejuni-colonization pattern between age goups.     

Long-term antibody responses following human infection with Campylobacter jejuni

Epidemiological evidence suggests prior infection of humans by Campylobacter jejuni leads to protection against disease following further exposure. It is known that infections elicit strong antibody responses following the onset of disease and that antibody levels are elevated in putatively immune populations. To determine if systemic and mucosal antibodies induced by a confirmed infection remain at elevated levels for prolonged periods, repeat serum, saliva and urine samples were taken from campylobacter patients from 1 week and up to a year postinfection. Antibodies were monitored by ELISAs using three different antigen preparations: acid-glycine extracts (AE) of C. jejuni strain 81116 and an aflagellate mutant (R2), and a whole-cell R2 sonicate, and by Western blotting. Levels of serum IgG antibodies against 81116AE and R2 sonicate, but not R2AE, remained significantly raised over time when compared to a comparison population. Serum anti-sonicate IgA antibody levels were initially significantly raised but decreased over time to levels similar to the comparison group. There were no significant differences in levels of salivary IgA against the AEs. Anti-sonicate salivary IgA and IgG levels were initially significantly higher than in the comparison group. Both declined over time but the IgG levels remained significantly higher. Significant correlations were seen between serum IgG levels and age and duration of illness. Serum antibodies against flagellin, 40 kDa and 29 kDa antigens were still detectable in most patients up to a year postinfection, as were salivary antibodies to flagellin, the major outer-membrane protein and a 40 kDa antigen.     

Campylobacter jejuni antibodies in Nigerian children.

Titers of complement-fixing (CF) antibody to Campylobacter jejuni were demonstrated in 87 (36.7%) of 237 infants 6 to 15 months old in Jos, Nigeria. Of the total number of children examined, 81 had acute diarrhea and 27 of them (33.3%) were found to have CF antibodies in their serum. The remaining 156 children were asymptomatic, and 60 (38.4%) of them had CF antibodies. In the diarrheal group, 27 of 75 children 6 to 8 months old were CF antibody positive. There was no significant difference in the incidence of CF C. jejuni antibodies in the diarrheal and nondiarrheal infants (P greater than 0.05). Also, infants 9 to 15 months old had a higher incidence of CF antibodies (46.5%) than those 6 to 8 months of age (25%). The data suggest that the infants whose sera were CF antibody positive had had an exposure to C. jejuni. All 33 infants 6 to 8 months of age who had no diarrhea were CF antibody negative.     

Antigenicity of Campylobacter jejuni flagella.

We studied the antigenicity of a wild-type flagellate and motile (F+M+) Campylobacter jejuni strain (81116) and two daughter mutants, one flagellate and immotile (F+M-) and one aflagellate and immotile (F-M-). By sodium dodecyl sulfate-polyacrylamide gel electrophoresis of acid-extracted surface proteins, a 63-kilodalton (kDa) band identified from sheared flagella as the flagellar protein was present in the F+M+ and F+M- strains but not in the F-M- strain. No other differences in protein profile among the three strains were noted. By Western blotting, serum from rabbits immunized with either the F+M+ or F-M- strain detected a 63-kDa protein in the F+M+ and F+M- strains but not in the F-M- strain. That the F-M- antiserum recognized the 63-kDa band suggests that small amounts of this protein or a cross-reacting antigen is present on the F-M- strain. By counterimmunoelectrophoresis of the acid-extracted preparations with immune sera, all three strains were found to share three major antigens, but a fourth antigen with a net positive charge was present only in the F+M+ and F+M- strains. Antisera to five C. jejuni and two Campylobacter fetus strains recognized the 63-kDa protein of purified F+M+ flagella in Western blots, demonstrating a common antigen is present, but enzyme-linked immunosorbent assay results suggest that the sharing of this antigen among Campylobacter strains is variable.     

Chemotactic behavior of Campylobacter jejuni.

The chemotactic behavior of Campylobacter jejuni was determined in the presence of different amino acids, carbohydrates, organic acids, and preparations and constituents of mucin and bile. L-Fucose was the only carbohydrate and L-aspartate, L-cysteine, L-glutamate, and L-serine were the only amino acids producing a chemotactic (positive) response. Several salts of organic acids, including pyruvate, succinate, fumarate, citrate, malate, and alpha-ketoglutarate, were also chemoattractants, as were bile (beef, chicken, and oxgall) and mucin (bovine gallbladder and hog gastric). Most constituents of bile tested individually were chemorepellents, but the mucin component was chemoattractant. The chemotactic behavior of C. jejuni toward L-fucose, a constituent of both bile and mucin, may be an important factor in the affinity of the organism for the gallbladder and intestinal tract.     

Electron microscopy of Campylobacter jejuni.

Stools from 56 patients with gastroenteritis were cultured for Campylobacter jejuni. The five strains isolated were examined by electron microscopy. The campylobacter cells were pleomorphic and most displayed appearances similar to those of V. fetus. Morphological changes were observed in cultures subjected to prolonged incubation.